Self-opening tool



May 26, 1931.

'.1. v. WALKER sELFpPENING TooL- v Filed Feb. 27, 1929 'IES 3 V. Q M 6 m a M a H ./J 9 m 7 4FM 6 J 0n v T 6, Wm i 4 M 3/ M f 2 fr 5 MN@ :52;: {d} w a4. H L

Patented May 26, 1931 narran stares PATE-Nr orrica JOHN V. W'ALKER, OF FAIRVIEW, PENNSYLVANIA, ASSIGNO'B. TO .i TITAN TOOL CON'- YANY, 0F EBEE, PENNSYLV 11325, A CGELECEATIGN OF EENNSYLVANIA sans-eremita troonv Application 4iiled February 2'?, 1929.

Self-opening to-ols have many uses. The present invention is particularly designed tor driving studs and provides a very rugged, simple and eiiicient structure for this purpose. Features and details oil the invention will appear trom the specitication and claims.

A preferred embodiment of the invention is illustrated in the accompanying drawings as follows z- Fig. 1 is a vertical sectional view oi' the device. j

Fig. 2 a bottom view ot the device.

Fig. 3 a sectional view corresponding to hat or" Fig. 1 showing the device in open position.

Fig. 4 a perspective view ot an opening and spreading cap tor the device.

1 marks the work having a screw-threaded opening 2 into which a stud 3 is being driven.

Jaws l are ot separable torni and have threads 5 on their inner faces adapted to engage the threads ot the stud and have tapered surfaces 6 at their outer peripheries engaging a tapered surface 7 in a driving sleeve 8. The tapered surface 7 is ot polygonal form. its shown it is oi hexagonal form and the tapered surfaces ot the jaws conform to the surfaces ot the head with the jaws in closed position, each jaw comprising one angle and two sides ot the periphery. The head 7 has a cylindrical surface 8a extending from the tapered portion and the jaws have cylindrically* shaped Shanks 9 extending into this portion. The jaws are each provided with an axiallyextending groove 10, the upper end 11 of the roove forming a stop shoulder. Locking pins 12 are carried by screws 13 in the wailV ot the sleeve 8. These against rotation relatively to the head, or in any event locate them initially so that when they close the angles ot the tapered portions oi the jaws register with the angles ot the socket so that there is an immediate engage'- ment ot these surfaces giving a rigid wrenchhold of the jaw by the head.

The jaws are provided with peripheral grooves 14 at their ends and a split ring 15 is arranged in this groove. An opening plug 16 has a tapered end 17 operating on tapered surfaces on the Vinside ot the jaws 4. This pins lock the jaws Y comprises a tapered Serial No. 342,990.

plug has an extension 18 around which a coiled spring 19 is arranged and this oper. ates against a pressure and separating plat-e 20. This has extensions 21 which entend into a peripheral groove22 on the insides of the jaws at their upper ends. The plate 20 has projections 20a which extend into the space between the jaws and thus maintain the sep-V aration ot the jaws. A screw 23 extends through the plate 20 into the extension 18` andY limits the outward movement of the opening plug, as indicated in'Fig. 3. The screw eX- tends into a socket 211 in the head and the jaws are closed.

ln the operation of the device when the article is pressed downwardly on to a stud, the stud engaging the opening plug 17 forces the jaws upwardly into the socket firmly seating the polygonal outer periphery ot these jaws into the tapered `socket at the lower end ot lthe head. This gives a very positive and secure wrench-hold directly at the driving end of the head. its limit ot movement the driving head is preferably allowed to yield through a slip driving device, any slip driving device accomplishing the purpose, the one specifical-l l shown and hereinafter described being suitable tor that'purpose. When the stud has been driven andthe head retracted the jaws are opened by the opening this disengages the threads ot the jaws trom the threads ot the stud and permits ot the withdrawal ot the tool. `The head is provided with a shanlr 8a and is connected by any suitable connecting device with a slip driving device. -This slip driving device outer member 25 con nected with thehead, and a tapered inner member 2G operating inthe outer member. The tapered inner member is connected with a source ot power by a shank 27. f A flanged sleeve 28 engages a `shoulder 29 at the upper end ot the inner tapered member and is locked with the outer tapered member by a spline 30. An adjusting nut 31 operates on screw threads 25a on the outer member and screw threads 32 on the sleeve 28. TheV threads 25al and 32 are ot dierent pitch giving a very nice adjustment ot the tapered l/Vhen the stud reaches' plug and portions. A nut 33 is arranged on screw threads 34 on the shank and locks the sleeve 28 against upward movement. This slip driving device operates in the ordinary manner. It is adjusted to have a driving action with as kmuch power :as desired rand lto slip where greater resistance is encountered.

lVhat I claim as new is:` Y l. In a self-opening tool, the combination 10 of a head having a tapered socket, saidsocket .having a peripheral wall of polygonal form; separable jaws in the socket conforming approximately when closed to the socket walls; a mounting for said `jaws slidable in the 15 head to open and close the jaws; and spring- Y a bottoming surface with .the jaws .in closed p0 position, and a spring `exerting `pressure on the plug.

2. Ina self-opening tool, the combination of a head having a tapered socket, said socket having a peripheral `wallof polygonal form;

z5 separable .jaws in the socket Iconforming lapproximately when closed to the socket walls; a lmounting for said jaws slida'ble in .thehead to open and :close the jaws.; and spring-actuated means opening the jaws, comprising 30 a 'plug having' wedging .surfaces slidingly mounted within the jaws said plug forming a hottoming surface with the jaws in closed position, .a spring' exerting pressure on the plug', and a Vstop limiting .the outward move- C5 ment of the plug.

3. In a self opening tool, the vcombination of ahead having a .tapered socket, vthe `opening vend of the socket having a peripheral wall of polygonal form; separable jaws wit-,hin the socket having an outer periphery substantially conforming to the socket and each jaw vhavingan angle and two s idesconformingtofanangleandftwo sides in the periphery of the socket and said jaws .havingaxially extending grooves; pins carried by the fhead extending into the grooves; a plug arranged within the jaws, said plug terminating in inclined walls achpted to open the jaws; a spring .operating on the plug; a. base for the Jiplug anchored on the jaws, .said plug forming bottoming surface with the jaws in closed position;-Y and a screw extending through the baseand limiting the outermovementof the plug'. j

L! In testimony whereof I have hereunto set my hand.

' JOI-IN V. IVALKER. 

